NASHVILLE - Tennessee Transportation Commissioner Gerald Nicely says he realizes he may have a tough time persuading motorists to pay tolls in a state that hasn't charged drivers since the 1920s to roll across asphalt.

"We would have a great deal of educating to do with the public and the Legislature before we would be able to enact a toll," Nicely said. "Some people say they're already paying gas taxes, so this would be double taxation."

Last year, Nicely commissioned a study by the engineering firm Wilbur Smith Associates to look at the feasibility of charging tolls on three potential Tennessee routes. He's expected to release the results of that study when he addresses lawmakers this week.

The three projects were the Knoxville Regional Parkway, also called the Orange Route; a bridge over the Cumberland River to provide access to Nashville from Hendersonville; and a road that would diverge from Interstate 40 near Strawberry Plains and lead to Gatlinburg.

"We tried to pick candidates that could be tolls based on other states' roads," said Ed Cole, TDOT's chief of environment and planning.

He added that proposed toll legislation would apply only to future roads and possibly the carpooling lanes found in Nashville and Memphis.

Last month, Nicely told the Senate Transportation Committee that decreases in federal funding are making road projects more difficult to fund.

Gov. Phil Bredesen has acknowledged that Tennessee may have to increase its gasoline tax of 21.4 cents per gallon some time over the next four years to make up for shortfalls, and he said toll roads may be able to alleviate some of that pressure.

When he talks to lawmakers this week, Nicely is expected to explain what road projects the state won't be able to afford without a change in the funding formula. TDOT's 10-year road plan is facing a $2 billion shortfall, officials said.

For now, Nicely said he is proposing only the authority to impose tolls, as is done in 26 other states. He's not asking for laws that would allow private/public partnerships in building roads, which several other states have embraced.

"We are asking that it be an available option," Nicely said of tolls. "It's something we would do only with strong local support. But I do think it's something we need as a tool."

Mark Richey, president of Citizens Against the Beltway Orange Location, said he can't envision people supporting a toll on the Knoxville parkway. The group formed in 1997 to fight the Orange Route and has retained a lawyer to continue the battle.

"People are not going to pay the toll until traffic backs up downtown and makes it worthwhile to pay the toll; that's human nature," Richey said.